Chevrolet 1988 Light Duty Truck Repair Manual page 356

41-4 2.5 LITER L4 ENGINE
DISASSEMBLY OF THE ENGINE
1. O uter Engine Heat Stove
2. Bolt
3. Stud
4. Stud
5. Exhaust Manifold
6. Inner Engine Heat Stove
7. Exhaust Manifold Gasket
8. Stud
9. Bolt
,10. Coolant F itting
11. Gasket
12. Therm ostat
13. Therm ostat Housing
14. Bolt
15. Hose Clamp
16. Hose
TOOLS AND SHOP EQUIPMENT
A clean, well lit work area should be available. Other
necessary aids include: a suitable parts cleaning tank,
com pressed air supply, trays to keep parts and fasteners
organized, and an adequate set of hand tools.
An approved engine repair stand will aid the work and
help prevent personal injury or damage to engine com ­
partments.
Special tool are illustrated throughout this section, and
are listed at its end. These tools (or their equivalents) are
specially designed to quickly and safely accom plish the
operations for which they are intended. The use of these
tools will also m inim ize possible dam age to engine com ­
ponents.
Some precision m easuring tools are required for in­
spection of certain critical components. Torque wrenches
will be necessary for correct assem bly of various parts.
ACCESSORY REMOVAL
This manual assum es that the engine accessories have
been removed. These accessories may include one or
more of the following:
Hydraulic Pump
Generator TBI Unit
D istributor
It is beyond the scope of this section to detail the many
different accessory installations. Refer to the proper Truck
Service Manual for this inform ation.
Diagram s of em ission and vacuum hose routings,
wiring harness routings, accessory drive belt layout, etc.,
should be made before removing accessories.
17. C ylinder Head Gasket
18. Intake Valve
19. Exhaust Valve
20. Plug
21. Gasket
22. Coolant Temperature Sensor
24. Cylinder Head
25. C ylinder Head Bolt
26. Spark Plug
27. Cylinder Head Bolt
28. Valve Spring Cap
29. Valve Stem Oil Seal
30. Valve Keys
31. Rocker Arm Ball Bolt
32. Rocker Arm Ball
33. Valve Rocker Arm
Figure 2— Cylinder Head, Manifolds, and Com ponents
Cooling Fan
34. Valve Stem Oil Shield
35. Valve Spring
36. Intake Valve Stem Seal
37. Washer
38. Intake M anifold Bolt
39. Plug
41. Plug
42. Intake M anifold Stud
43. Intake Manifold
44. Intake M anifold Gasket
45. Push Rod Guide
46. Cylinder Head Bolt
47. Push Rod
48. Rocker Arm Cover
CLEANING
Remove the engine accessories before cleaning to
provide better access to engine exterior surfaces. After
removing the TBI unit, distributor, fuel pump, oil filter, etc.,
cover the openings with tape to prevent the entry of water,
solvent, and dirt.
Methods used to clean the engine will depend on the
aids w hich are available. Steam cle a nin g , pressure
w a sh in g , or so lve n t c le a n in g are som e a c ce p ta b le
methods. Allow the engine to dry before beginning the
work.
It is im portant that the engine be as clean as possible to
p re v e n t d ir t fro m e n te r in g
disassembly.
PARTS IDENTIFICATION
Refer to figure 2 through 5.
DRAINING THE ENGINE
R em o ve or D is co n n e c t (F ig u re 5)
• Oil drain plug (73). Allow the oil to drain.
• Oil filter.
Install or C o n n ect (F ig u re 5)
1. Oil drain plug (73).
T ig h ten
• Oil pan drain plug to 34 N m (25 ft. lbs.).
F-01980
c r itic a l a re a s d u rin g